127.0.0.0 - 127.255.255.255
NetType: IANA Special Use
Comment: This block is assigned for use as the Internet
Comment: host loopback address. Datagrams sent to
Comment: addresses anywhere within this block loops back
Comment: inside the host. Many implementation only
Comment: support this for 127.0.0.1. This block was
Comment: assigned by the IETF in the Standard document,
Comment: RFC 1122 and is further documented in the Best
Comment: Current Practice document RFC 5735. These
Comment: documents can be found at:
Maybe xF defaults to that private IP if it can't determine the IP from the connection. But it isn't possible to get a connection from the internet on that IP. It's either coming from the local network your server is on ("Get out now! We traced the calls and they are coming from inside the house!"), or it's just a placeholder.
Dunno if you have access to this, but have you checked your raw access logs (or something similar). I used to own a server that, for some odd reason, 2 or 3 servers on the same network always did a scan of my site/server. We contacted the company and they said it was normal as it was one of their servers doing it (besides DNS, not sure why; there was no remote reboot option on that server). Each of those servers would scan my server at least 15x a day. Just a thought.
Is xenforo somehow tracking Apache internal dummy connections? They will show normally as 127.0.0.1/::1 on servers with IPv6 but as the whole 127 range is reserved I guess I understand it showing as 127.255.255.255
After thinking the issue was more fundamental, with Floris's help I was able to eliminate various server things, and then I realized that it was only happening with guests because of a integer filter on input. So fixed for the next release.
It turns out that when you use a int data type on a mysql table to store the iptolong value (integer representation of the ip address) the int datatype cannot contain all generated values. The numbers can be too large to be stored as a int.
The maximum int value will convert back into the 184.108.40.206 ip address.
Solution: change the datatype of the mysql field to a varchar - or float (I think 10 characters should do it - but not sure ... 12 will do for sure)